1. Technical Field
The present disclosure relates to a surgical fastener applying apparatus. More particularly, the present disclosure relates to a tool assembly for use with a surgical fastener applying apparatus, and methods of using the same, to apply a plurality of surgical fasteners to tissue with varying compressive forces. The present disclosure also relates to elastic members to apply and maintain constant compressive forces to tissue regardless of tissue thickness.
2. Background of the Related Art
There are several known types of surgical stapling instruments specifically adapted for use in various procedures such as end-to-end anastomosis, gastrointestinal anastomosis, endoscopic gastrointestinal anastomosis, and transverse anastomosis. Examples of stapling instruments for these various procedures can be found in U.S. Pat. Nos. 5,915,616; 6,202,914; 5,865,361; and 5,964,394.
Each surgical stapling instrument includes an anvil which is approximated relative to a staple cartridge. The staple cartridge typically has one or more laterally spaced rows of staples which, depending on the particular stapling instrument, may be arranged in a linear or non-linear configuration. The anvil includes staple forming depressions which are aligned with and/or in registration with the staple slots of the staples in the cartridge. In use, each of the surgical stapling instruments involves the gripping of tissue to be fastened, the ejecting of individual staples, the forcing of staples through the gripped tissue and the closing and/or forming of the staples against the staple forming depressions of the anvil.
A common issue in transecting tissue and/or in anastomosis procedures, employing any one of the surgical stapling instruments disclosed above, is the balance between anastomotic strength and the degree of hemostasis achievable. It is known to include different size staples in a surgical stapling apparatus having a constant gap (i.e., a uniform distance) between an anvil and a staple cartridge.